Patent GB-542082-A (GB)
Title: Improvements in or relating to the assembling of articles comprising a wire or wiresthreaded through an annular object of resilient material
IPC: H01R43/052
Filed: 1940-06-12
Abstract: 542,082. Assembling blasting detonators. ASHCROFT, D. G., and IMPERIAL CHEMICAL INDUSTRIES, Ltd. June 12, 1940, No. 10220. [Class 9 (i)] [Also in Group XXXVI] Means for threading insulated or other wires through an annular resilient member, such as a closure plug for insertion in a detonator which is then crimped round the plug, comprises a reciprocable, longitudinally separable needle adapted to be mounted in the aperture of the member and then to expand the member by separation of its parts to permit the wires to be threaded there-through, and means for removing the member from the needle as the latter returns. In Figs. 1, 3 and 5 the needle comprises spring-pressed members 1, 2 and during its forward motion, a plug 10 is placed in engagement, with a grooved base plate 3, Fig. 5 between spring-pressed members 4, 5, with extensions 6, 7, which, with spring-pressed gates 8, 9 hold the plug; the needle then passes through the plug and, as by cam action, its parts are separated to expand the plug and force apart parts 4, 5, 8, 9, to allow the wires to be threaded through the plug, after which the needle returns, parts 6, 7 grip the wires, and the gates 8, 9 strip the plug from.the needle. Cams &c. finally separate all the parts as in Fig. 5 to allow the threaded plug to be removed. In Fig. 10, the plugs are fed into position by a reciprocating member 12, and a circular ridge, 18 splays the plugs on entry of the needle 1, 2; the wires are fed through the needle into a reciprocable, rotatable member 13 with a spring-pressed plug 14 initially held by a cam 17 so that the widest part of a keyhole slot 15 receives the wires. The member 13 is then moved clear of the cam 17 and rotated to twist the wires, after which the plug and wires are removed, a fusehead is soldered to the ends of the wires, and the plug is secured in a detonator. In Figs. 14 and 15, a pivoted handle 84 reciprocates a carriage 87 between guides 88, the carriage carrying a cam rod 89 and two spring-pulled L-shaped levers 90 pivoted at 92 and carrying the parts 1, 2 and of the needle and rollers 94, 95 bearing against cams 96, 97; pairs of leaves 6, 7 and 8, 9 are pivoted at 102, 100 and pulled together by springs and hold the plug to be threaded. On advancing the lever 84 the needle penetrates the plug and between the gates 6, 7 and 8, 9 and the cams 96, 97 then cause separation of the parts of the needle and expansion of the plug to allow the latter to be threaded. At the end of the return stroke of handle 84 cams 96, 97 again separate the needle parts, while cam rod 89 separates the levers 6, 7 and 8, 9 to permit removal of the threaded plug. In a power driven machine, Figs. 17, 18, 19 and 21, a driven shaft 22 loosely carries a ratchet wheel 25 and pinion 24 connected by a spring 23 which normally grips shaft 22 to convey the drive through gear 26 to shaft 27; when stop 34, Fig. 19, holds ratchet wheel 25, spring 23 is freed to stop the drive. Stop 34 is carried by lever 32, pulled by the spring 40 and carrying a roller 35 adapted at two points in the cycle to enter recesses in a cam 28 on shaft 27, whereby the drive is stopped first to allow the plug to be threaded, and afterwards to allow the plug to be removed. The roller 35 is freed when desired by treadle 39 acting through link 38 and spring-pulled lever 37, a pin 42 acting through cam 43 to ensure release. Shaft 27 carries cams 29, 30, 31 of which cam 30 acts through roller 65, Fig. 17 and spring-pulled link 63 to reciprocate the needle carriage 61 acting as in Figs. 14 and 15, except that cams 78, 79, Fig. 25, replace cam rod 89, while cam 29 acts through lever 44, Fig. 18, pressed by spring 45, and link 46 to rock a toothed quadrant 49 which, through reducing gear 50 ... 53 and sleeve 54 rotates a shaft 55 which is reciprocated by its threaded end 56 engaging a nut and which carries the head 13 for twisting the wires as in Fig. 10; the reducing gear 50 ... 53 also through cam 58, bell crank 59 and link 60, oscillates a plug-feeding hopper 57 to prevent jamming of the plugs, while cam 31 oscillates a shaft 70, Fig. 21, and thereby, through lever 69 and link 68, reciprocates a slide 12 which feeds the plugs one by one from chute 82 to the working position. The needle may be in more than two parts.